Well, that's exactly what the large intestine does. It takes the remains of digested food — that is, food in which all the nutrients and minerals have been removed, and prepares it for elimination.

The Large Intestine and Its Functions

From the small intestine, any remaining food wastes pass into the large intestine. The
large intestine
is a relatively wide tube that connects the small intestine with the anus. Like the small intestine, the large intestine also consists of three parts: the cecum (or caecum), colon, and rectum. Follow food as it moves through the digestive system at
http://www.youtube.com/watch?v=Uzl6M1YlU3w
(1:37).

The
cecum
is the first part of the large intestine, where wastes enter from the small intestine. The wastes are in a liquid state. As they pass through the
colon
, which is the second part of the large intestine, excess water is absorbed. The remaining solid wastes are called
feces
. Feces accumulate in the
rectum
, which is the third part of the large intestine. As the rectum fills, the feces become compacted. After a certain amount of feces accumulate, they are eliminated from the body. A sphincter controls the anus and opens to let feces pass through.

Bacteria in the Large Intestine

Trillions of bacteria normally live in the large intestine. Most of them are helpful. In fact, we wouldn’t be able to survive without them. Some of the bacteria produce vitamins, which are absorbed by the large intestine. Other functions of intestinal bacteria include: